This invention relates to a method for casting or molding an article of jewelry, and more particularly, to a method for producing a bored out or hollow jewelry article such as a ring.
There are many well known processes used in the large volume production of jewelry. Such processes include die striking, casting and electroforming, all of which are used for producing metallic jewelry articles. Such production methods are capable of facilitating high volume, high speed production with very good reproducibility. For example, using permanent-mold casting or injection molding techniques, a single mold cavity may be used repeatedly to produce, at a low cost, a virtually unlimited number of jewelry articles of intricate detail and varying size.
In order to reduce production costs in the manufacture of jewelry articles, previous improvements have generally focused upon better equipment; very little effort has been directed to actually modifying the jewelry article that is produced in order to reduce the cost thereof. One way, of course, of reducing production costs is to reduce the amount of precious or semi-precious metal that is used in producing a jewelry article, while still achieving the visual presentation that is desired by the jewelry designer.
One such prior method involves the use of an acid or water-soluble wax insert disposed in a mold cavity in order to form a mold of a partially or completely hollow article. According to this technique, a soluble wax core insert is placed in a mold cavity. Then a molten wax is injected into the mold cavity, filling the cavity and surrounding the core insert. The core insert is then removed in order to produce a wax article having a hollow core.
In the prior art, the use of soluble wax core inserts has been less than desirable. In the first place, there have been difficulties in achieving proper alignment of the insert and in preventing random movement or shifting of the insert during waxing or casting. In addition, the prior art has failed to teach the use of a soluble wax core insert such that a hollow or bored out space is defined within the ring which extends virtually along the entire arcuate length thereof.
Moreover, in the prior art U.S. Pat. No. 5,718,278 to Baum, it is stated that it is not possible to produce a ring having an inner round radius design utilizing a vertically oriented mold configuration. However, the Baum process which utilizes a horizontally oriented mold configuration is less than desirable since it is not able to produce a ring which is hollowed or bored out to an arcuate content of 200° and up to or approaching 360°.
In the prior art patents to Hashimian et al, U.S. Pat. Nos. 6,453,699 and 6,554,052 there is taught a method for fabricating a hollow jewelry article which is bored out to an arcuate extent of 200° or greater.